School of Environment, Guangdong Engineering Research Center of Water Treatment Processes and Materials, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China.
School of Environment, Guangdong Engineering Research Center of Water Treatment Processes and Materials, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China.
Sci Total Environ. 2021 Aug 1;780:146639. doi: 10.1016/j.scitotenv.2021.146639. Epub 2021 Mar 21.
In present study, the effects of inorganic particles and their interaction with biofilms on the filtration behavior of dynamic membrane bioreactor (DMBR) were investigated. When no inorganic particles were included in the simulated domestic wastewater, a porous biofilm DM was formed on support materials. As a result, the transmembrane pressure (TMP) did not increase (< 10 Pa) during the 97 days' experiment and the effluent turbidity was consistently lower than 1.0 NTU. When sands (1.3-69.2 μm; 50 mg/L) were the only inorganic particles contained in wastewater, the effluent turbidity became instable and ranged from 0.31 to 3.88 NTU, probably because the DM structures were disturbed by sand scouring. The natural clays (0.5-2.7 μm) in wastewater were very liable to deposit on the support materials of DMBRs to form thick and compact DMs with greater contents of biomass and EPS, especially co-existing with sands. Due to the existence of natural clays, the DM porosity decreased significantly and rapid rising in TMP occurred frequently. This study demonstrated that pure biofilms without containing inorganic particles were ideal materials for DMs, which could achieve long-term stable operation with low effluent turbidity (< 1 NTU) and low TMP (< 10 Pa), while inorganic particles with any size could deteriorate the filtration performance. Therefore, removing the inorganic particles in wastewater as many as possible prior DMBR is critically important for achieving long-term stable operation.
在本研究中，考察了无机颗粒及其与生物膜的相互作用对动态膜生物反应器（DMBR）过滤行为的影响。当模拟生活废水中不包含无机颗粒时，支撑材料上会形成多孔生物膜 DM。因此，在 97 天的实验过程中，跨膜压力（TMP）没有增加（<10 Pa），出水浊度始终低于 1.0 NTU。当废水中仅含有砂粒（1.3-69.2 μm；50 mg/L）时，出水浊度变得不稳定，范围在 0.31 至 3.88 NTU 之间，这可能是因为 DM 结构受到砂粒冲刷的干扰。废水中天然粘土（0.5-2.7 μm）很容易沉积在 DMBR 的支撑材料上，形成具有更高生物质和 EPS 含量的厚而致密的 DM，特别是与砂粒共存时。由于天然粘土的存在，DM 的孔隙率显著降低，TMP 经常迅速升高。本研究表明，不含无机颗粒的纯生物膜是 DMBR 理想的 DM 材料，可以实现长期稳定运行，出水浊度低（<1 NTU），TMP 低（<10 Pa），而任何尺寸的无机颗粒都会恶化过滤性能。因此，在 DMBR 之前尽可能去除废水中的无机颗粒对于实现长期稳定运行至关重要。
